Abstract
Cold and diluted wastewater is a major challenge for nitrogen removal at wastewater treatment plants. The moving-bed biofilm reactor (MBBR) process has proven suitable for nitrogen removal under these conditions and several full-scale plants have been in operation for more than 20 years. These plants are still performing well, even at above design loads. Recently some of these plants have been evaluated for their low-temperature performance. In general, the results showed that temperatures down to 5 °C only had a minor impact on observed nitrification and denitrification rates. Higher dissolved oxygen concentrations can boost nitrification rates and are used as a tool to increase rates at low temperatures, thus partially compensating for the temperature effect. Post-denitrification rates were boosted by a controlled increase in carbon-to-nitrogen ratios at low temperatures. MBBR processes with combined pre- and post-denitrification are recommended for nitrogen-removal plants operating at low temperatures. Design recommendations and examples of flowsheets are given.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
More From: Water science and technology : a journal of the International Association on Water Pollution Research
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.